That is correct. A cheaper build can use insight, but the innovation here is using a +3 teleport base obsession and as many +all skills items as we can fit, to reduce the mana cost on teleport to a sustainable level. With obsession, enigma, ars baalos, shako, +2/20 crafted ammy, 2x soj, magefist, arach, anni, torch, sunder, cta buff, you get level 18 teleport with 7 mana cost, and at around 800-1000 mana and the regen enabled here, its enough you can just hold down teleport indefinitely.
The +3 teleport (sorceress only) from the base applies even if you are not a sorceress?